diff --git a/src/ca/cadef.h b/src/ca/cadef.h
index a42a388e8..8d92b6263 100644
--- a/src/ca/cadef.h
+++ b/src/ca/cadef.h
@@ -145,6 +145,7 @@ typedef struct ca_access_rights{
 
 
 /* Format for the arguments to user connection handlers 		*/
+struct channel_in_use;
 struct	connection_handler_args{
 	struct channel_in_use	*chid;	/* Channel id	 		*/
 	long			op;	/* External codes for CA op	*/
@@ -941,7 +942,11 @@ void *  /*      PVALUE  R       pointer to new channel value of type    */
 /*
  * print status of a sync group
  */
+#ifdef CAC_FUNC_PROTO
 int epicsShareAPI ca_sg_stat(CA_SYNC_GID gid);
+#else /*CAC_FUNC_PROTO*/
+int epicsShareAPI ca_sg_stat();
+#endif /*CAC_FUNC_PROTO*/
 
 /*
  * CA_MODIFY_USER_NAME()
diff --git a/src/ca/caerr.h b/src/ca/caerr.h
index df3437504..79551946b 100644
--- a/src/ca/caerr.h
+++ b/src/ca/caerr.h
@@ -48,6 +48,7 @@
 #define INCLcaerrh
 
 #include <shareLib.h>
+#include <epicsTypes.h>
 
 #ifndef HDRVERSIONID
 #       define HDRVERSIONID(NAME,VERS)
@@ -153,9 +154,9 @@ HDRVERSIONID(caerrh, "@(#) $Id$")
 
 
 #ifndef CA_ERROR_GLBLSOURCE
-epicsShareExtern const char	*ca_message_text[];
+epicsShareExtern READONLY char	*ca_message_text[];
 #else
-const char	*ca_message_text[]
+READONLY char	*ca_message_text[]
 =
 {
 "Normal successful completion",
@@ -212,6 +213,10 @@ const char	*ca_message_text[]
 };
 #endif
 
-const char *ca_message(long ca_status);
+#ifdef __STDC__
+READONLY char *ca_message(long ca_status);
+#else /* __STDC__ */
+READONLY char *ca_message();
+#endif
 
 #endif
diff --git a/src/include/cadef.h b/src/include/cadef.h
index a42a388e8..8d92b6263 100644
--- a/src/include/cadef.h
+++ b/src/include/cadef.h
@@ -145,6 +145,7 @@ typedef struct ca_access_rights{
 
 
 /* Format for the arguments to user connection handlers 		*/
+struct channel_in_use;
 struct	connection_handler_args{
 	struct channel_in_use	*chid;	/* Channel id	 		*/
 	long			op;	/* External codes for CA op	*/
@@ -941,7 +942,11 @@ void *  /*      PVALUE  R       pointer to new channel value of type    */
 /*
  * print status of a sync group
  */
+#ifdef CAC_FUNC_PROTO
 int epicsShareAPI ca_sg_stat(CA_SYNC_GID gid);
+#else /*CAC_FUNC_PROTO*/
+int epicsShareAPI ca_sg_stat();
+#endif /*CAC_FUNC_PROTO*/
 
 /*
  * CA_MODIFY_USER_NAME()
diff --git a/src/include/caerr.h b/src/include/caerr.h
index df3437504..79551946b 100644
--- a/src/include/caerr.h
+++ b/src/include/caerr.h
@@ -48,6 +48,7 @@
 #define INCLcaerrh
 
 #include <shareLib.h>
+#include <epicsTypes.h>
 
 #ifndef HDRVERSIONID
 #       define HDRVERSIONID(NAME,VERS)
@@ -153,9 +154,9 @@ HDRVERSIONID(caerrh, "@(#) $Id$")
 
 
 #ifndef CA_ERROR_GLBLSOURCE
-epicsShareExtern const char	*ca_message_text[];
+epicsShareExtern READONLY char	*ca_message_text[];
 #else
-const char	*ca_message_text[]
+READONLY char	*ca_message_text[]
 =
 {
 "Normal successful completion",
@@ -212,6 +213,10 @@ const char	*ca_message_text[]
 };
 #endif
 
-const char *ca_message(long ca_status);
+#ifdef __STDC__
+READONLY char *ca_message(long ca_status);
+#else /* __STDC__ */
+READONLY char *ca_message();
+#endif
 
 #endif